<template>
  <el-container class="home-container">
    <!-- 头部区域 -->
    <el-header>
      <div>
        <img src="../assets/System.png" alt width="48px" />
        <span>电商后台管理系统</span>
      </div>
      <el-button type="info" @click="logout">退出</el-button>
    </el-header>
    <!-- 页面主体区域 -->
    <el-container>
      <!-- 侧边栏 -->
      <el-aside :width="isCollapse ? '64px': '200px'">
        <!-- 侧边栏折叠/展开转换 -->
        <div class="toggle-button" @click="toggleCollapse">|||</div>
        <!-- 侧边栏菜单区域 -->
        <el-menu
          background-color="#333744"
          text-color="#fff"
          active-text-color="#409eff"
          :unique-opened="true"
          :collapse="isCollapse"
          :collapse-transition="false"
          :router="true"
          :default-active="activePath"
        >
          <!-- 一级菜单 -->
          <el-submenu :index="item.id + ''" v-for="item in menuList" :key="item.id">
            <!-- 一级菜单的模板区域 -->
            <template slot="title">
              <!-- 图标 -->
              <i :class="iconsObj[item.id]"></i>
              <!-- 文本 -->
              <span v-text="item.authName">菜单名称</span>
            </template>
            <!-- 二级菜单 -->
            <el-menu-item
              :index="'/' + subItem.path"
              v-for="subItem in item.children"
              :key="subItem.id"
              @click="saveNavState('/' + subItem.path)"
            >
              <template slot="title">
                <i class="el-icon-menu"></i>
                <span v-text="subItem.authName">菜单名称</span>
              </template>
            </el-menu-item>
          </el-submenu>
        </el-menu>
      </el-aside>
      <!-- 右侧内容主体 -->
      <el-main>
        <router-view></router-view>
      </el-main>
    </el-container>
  </el-container>
</template>

<script>
export default {
  data() {
    return {
      menuList: [],
      iconsObj: {
        125: 'el-icon-user-solid',
        103: 'el-icon-lock',
        101: 'el-icon-s-goods',
        102: 'el-icon-s-order',
        145: 'el-icon-s-data'
      },
      isCollapse: false,
      // 被激活的导航链接地址
      activePath: ''
    }
  },
  created() {
    this.getMenuList()
    this.activePath = window.sessionStorage.getItem('activePath')
  },
  methods: {
    logout() {
      window.sessionStorage.clear()
      this.$router.push('/login')
    },
    async getMenuList() {
      // 获取左侧菜单栏数据
      const { data: res } = await this.$http.get('menus')
      if (res.meta.status !== 200) return this.$message.error(res.meta.msg)
      this.menuList = res.data
    },
    toggleCollapse() {
      // 点击按钮切换侧边菜单的折叠与展开状态
      this.isCollapse = !this.isCollapse
    },
    saveNavState(activePath) {
      // 保存导航栏链接的激活状态
      window.sessionStorage.setItem('activePath', activePath)
      this.activePath = activePath
    }
  }
}
</script>

<style lang="less" scoped>
.home-container {
  width: 100%;
  height: 100%;
}

.el-header {
  background-color: #373d41;
  display: flex;
  // 左右贴边对齐
  justify-content: space-between;
  // padding-left: 0;
  align-items: center;
  color: #fff;
  font-size: 28px;
  font-weight: bold;
  > div {
    display: flex;
    // 纵向居中对齐
    align-items: center;
    span {
      margin-left: 15px;
    }
  }
}

.el-aside {
  background-color: #333744;
  .el-menu {
    border: none;
  }
}

.el-main {
  background-color: #eee;
}

.toggle-button {
  background-color: #4a5064;
  font-size: 10px;
  text-align: center;
  line-height: 24px;
  color: #fff;
  letter-spacing: 0.2em;
  cursor: pointer;
}
</style>
